1. Field of the Invention
This invention relates to new compositions comprising hazardous products but which are nevertheless safe for handling and the environment.
2. Discussion of the Prior Art
At present, most hazardous liquids are stored in metal drums or, where smaller quantities are required, in plastic containers.
Hazardous compounds, especially agrochemical compounds, are formulated in various compositions. Liquid compositions are most convenient for farmers because of the relative ease with which they can be handled. There are, nevertheless, difficulties in handling such liquid compositions. There is a danger of spillage or leakage if there are holes in the containers previously used or if they are dropped. Although secure containers resistant to shock can be used, in the event of an accident, for example during transportation, the risk remains of spillage or leakage with rapid loss of liquid, for example leaking onto the ground. There is also a danger of splashing when the farmer is putting the liquid in a tank with water.
It has been difficult to provide a formulation and a container system which safeguards the environment and those handling it, including farmers and transporters.
An object of the instant invention is to provide a new formulation system to contain agrochemicals which is safe for people and the environment.
Another object of the instant invention is to provide a new formulation system for agrochemicals which is easy to put in a containing system and easy to manipulate by the farmer.
Another object of the instant invention is to provide a new formulations system for agrochemicals which is readily soluble and/or dispersible in water.
Another object of the instant invention is to provide a new formulations system for agrochemicals which is as much condensed as possible, using the least amount of space.
Another object of the instant invention is to provide a new formulations system to contain hazardous compounds, e.g., agrochemicals, which diminishes the risks of pollution.
It is also known that liquid agrochemicals may be contained in soluble bags or sachets made from films. Such systems are useful and helpful, but may be improved because the films may crack and break and thus cause spillage of the contained agrochemicals and create contamination problems. In fact, there are a variety of defects which may be present in films, which lead to weaknesses of film and consequently a potential source of leakage. The presence of air bubbles, of dust particles or foreign materials, of gel particles or thin areas on or in the film are all potential weak points. If a film with such weak points is subjected to a lot of handling or physical shock, the film may fail at that point. This is especially a problem in the agrochemical industry where containers may be subjected to rough or unsafe handling by distributors or farmers.
Another object of the instant invention is to avoid leakage through pinholes when an agrochemical containing bag is used. Such pinholes are rare, but only one pinhole among thousands of bags is enough to cause a lot of trouble; because the liquid going through the pinhole contaminates its environment.
Another object of the instant invention is to avoid breakage of the container which contains an agrochemical formulation. When the container is rigid, there is a certain possibility of simple breakage. With a liquid in a bag this possibility is somewhat reduced, but the liquid still transmits the shocks and there is the problem of hydraulic hammer effect. An object of the instant invention is to avoid, or at least to partially reduce, this hydraulic hammer effect. It has been proposed to reduce the possibility of breakage by means of an air space in the bag, but this represents some loss of storage space.
Another object of the present invention is to have a formulation or composition for hazardous compounds which dissipates, as much as possible, the energy of a shock to a container from outside.
Another object of the present invention is to provide a shock absorbing formulation system for containing agrochemicals, e.g., pesticides (especially herbicides, insecticides, fungicides, acaricides or nematocides) or plant protection agents or plant growth regulators or plant nutrients.
It was known to use gel formulations for pharmaceuticals or cosmetics, but the technical problems and the solution for solving such problems are very different:
there is practically no risk of polluting or contaminating of the environment when handling such products, in contrast to pesticides and agrochemicals PA1 it is generally sufficient for such gels to have a water insoluble package PA1 there is practically no exposure to air humidity PA1 the size of gels used for pharmaceutical or cosmetical purposes is generally very small. PA1 a surfactant; PA1 a thickener and/or a gelling agent; PA1 an organic solvent (as used herein this word includes a mixture of individual solvents) which is miscible (or at least emulsifiable) with water, and preferably such that the hazardous product is soluble in the mixture of this solvent and water at the given concentration; PA1 a dispersant; PA1 a secondary thickener; or PA1 other additives, such as stabilizer(s), antifoaming agent(s), buffer(s) or antifreezing agent(s).
Thus it was unobvious to obtain gels which are convenient for water soluble sachets or bags, or for agrochemicals containing water soluble sachets or bags, or for shock absorption purposes for such bags.
Another possibility is to have agrochemicals in the form of wettable powders in a bag which may be water soluble. However, not all agrochemicals may be used in the form of a wettable powder, and even when these powders are wettable, the time to wet the powder (wetting time) may be too lengthy to be practical.
As already discussed, other containing systems for pesticides which are safe for the environment have been proposed in the past, especially those containing liquid in soluble bags or sachets. However, up to now the liquids which have been used are hydrophobic and non-aqueous liquids because aqueous liquids can damage the walls of the water soluble bags which contain them, especially for large bags such as one liter bags. Unfortunately, there is a general trend in agriculture to use more and more aqueous formulations because such formulations are safer for the environment and for the people who handle the agrochemicals. Furthermore, some agrochemical compounds can only be formulated in aqueous medium, such as amine salts of pesticides, so that the non-aqueous formulations cannot be used for them, nor the water soluble bags containing a non-aqueous formulation.
In patent application WO 89/04282 it has been proposed to have aqueous syrup compositions in water soluble bags. That invention is based on the use of osmosis phenomenon which requires a high concentration of syrup in the composition. The concentration may be increased, of course, by decreasing the amount of water. However, this is detrimental to the dispersibility of an agrochemical composition during tank mixing in the field. The concentration of syrup may be increased by adding sugar, but this is not realistic for agrochemical compositions, for many reasons. Chief of them is that sugar, especially large amounts of sugar, may transform the agrochemical composition to a kind of bait for warm blooded animals, which is especially undesirable in order to get environmentally safe products. Also, the syrup may cause fermentation yielding gas and pressure in the stored product thus shortening the useful life of the agricultural formulation.
The present invention seeks to provide a new aqueous formulations system for hazardous chemicals, especially agrochemicals, which does not damage the water soluble bags containing them and which is based on a completely different principle than the above known packaging technology.
The invention further seeks to provide a new formulation system for agrochemicals which quickly dissolves when put into water and which is not damaged by normal freezing.
Other objects of the invention will better appear from the following description. The objects of the invention can be achieved in full or in part by means of the invention.